The present invention relates to updating a memory of a telecommunications terminal, and it relates more particularly to methods and devices for updating a memory, e.g. a cache memory, of a telecommunications terminal on the basis of data stored in a subscriber identity module for a subscriber to a mobile telephony network with which the terminal can co-operate.
The invention finds a particular but non-limiting application in optimizing the updating of a cache memory of a telecommunications terminal, e.g. of the wireless type.
In known manner, wireless telecommunications terminals, e.g. such as mobile telephones or the equivalent, are designed to co-operate with an identity module of a subscriber to a mobile telephony network, also known as a universal integrated circuit chip (UICC) or as a UICC module, in order to be able to communicate with a given telecommunications network. A UICC module is sometimes also commonly referred to as a SIM card. A subscriber identity module may be embodied in an embedded or removable component of the secure element type (eSE or SE) constituted by a chipset that is distinct from the main terminal of the mobile terminal. By way of example, the subscriber identity module may satisfy the specifications of ISO 7816 (ETSI standard TS 102 223), or indeed the common criteria standard (ISO/CEI 15408). It can dialog with the mobile terminal in which it is embedded or incorporated, by using application protocol data unit (APDU) frames.
The UICC module enables the mobile telephone in which it is generally inserted or embedded to interact with a telecommunications network. To do this, the UICC module contains information for accessing the network, in particular a unique “international mobile subscriber identity” (IMSI) associated with a particular subscription of a user with the associated telephony operator.
The UICC module also generally includes data stored in elementary files. By way of example, an elementary file may contain contact data of an address book (telephone number, name, address, etc.), SMSs, or other useful information.
By way of example, a mobile telephone using a UICC module can access such elementary files when interacting with the user or with the telecommunications network.
Because of the relatively long length of time needed by the telecommunications terminal to access data contained in the elementary files of the UICC module, and given the repeated access thereto while the terminal is in operation, the terminal (or more precisely a communications interface of the terminal such as a modem, for example) may be configured to store copies of the elementary files of the UICC module in a cache memory of the terminal in order to reduce access times.
Thus, during a stage of the user starting the telecommunications terminal, the terminal generally performs a complete update of its cache memory by storing all of the elementary files that it recovers for this purpose from the UICC module.
Unfortunately, while updating the cache memory in this way, the terminal must necessarily read and copy into the cache memory all of the elementary files of the UICC module, even though only some of these files have actually been modified since the most recent operation of updating the cache memory.
In other words, the Applicant has observed that, on starting, the terminal must necessarily read and copy all of the data in the elementary files of the UICC module, including data that, a priori does not need to be updated in the cache memory. Furthermore, the number of applications and services implemented on the UICC module is tending to increase, so the access time required on starting in order to read the data from the elementary files is also increasing to the detriment of the speed of execution and the general quality of the user experience.
Thus, there exists a need for a solution that, during a stage of starting the telecommunications terminal, enables a memory of the terminal (e.g. a cache memory) to be updated quickly and more effectively on the basis of the data contained in the UICC module.